MSSQL 查询：如何按每个分区查找不正确的行？

Question

我需要根据逻辑找出不正确的行。

逻辑是：

如果child有行（我会调用第一行）

| merit     | fruit | vegetable |
| --------- | ----- | --------- |
| behaviour | apple | cucumber  |

然后在 merit = poem 和 fruit = apple 的行中必须是 only vegetable = cucumber（黄瓜无其他字） (是第二行)

| merit | fruit | vegetable |
| ----- | ----- | --------- |
| poem  | apple | cucumber  |

AND第二行的时间间隔必须比第一行的时间早或晚4小时，作为正确的例子：

| child_id  | date            | merit     | fruit | vegetable |
| --------- | --------------- | --------- | ----- | --------- |
| 2         | 1/26/2022 16:00 | poem      | apple | cucumber  |
| 2         | 1/26/2022 18:00 | behaviour | apple | cucumber  |

可以看到，是4小时间隔

我有 table:

| child_id  | date            | merit       | fruit   | vegetable |
| --------- | --------------- | ----------- | ------- | --------- |
| 1         | 1/27/2022 14:00 | behaviour   | apple   | cucumber  |
| 1         | 1/27/2022 15:00 | poem        | apple   | carrot    |
| 1         | 1/27/2022 17:00 | sleep       | apple   | ginger    |
| 1         | 1/27/2022 20:00 | competition | berry   | tomatoe   |
| 2         | 1/26/2022 13:00 | sleep       | apricot | tomatoe   |
| 2         | 1/30/2022 13:00 | poem        | apple   | cucumber  |
| 2         | 1/29/2022 13:00 | poem        | apple   | cucumber  |
| 2         | 1/26/2022 16:00 | poem        | apple   | cucumber  |
| 2         | 1/26/2022 18:00 | behaviour   | apple   | cucumber  |
| 2         | 1/26/2022 19:00 | present     | apple   | broccoli  |
| 3         | 1/25/2022 11:00 | present     | orange  | cucumber  |
| 3         | 1/25/2022 13:00 | poem        | apple   | ginger    |
| 3         | 1/25/2022 15:00 | behaviour   | apple   | cucumber  |
| 4         | 1/26/2022 14:00 | behaviour   | apple   | cucumber  |
| 4         | 1/27/2022 21:00 | poem        | apple   | carrot    |
| 4         | 1/27/2022 15:00 | poem        | apple   | carrot    |
| 4         | 1/27/2022 20:00 | sleep       | apple   | ginger    |
| 4         | 1/27/2022 21:00 | competition | berry   | tomatoe   |

我期望的结果：

| child_id  | date             | merit | fruit | vegetable |
| --------- | --------------- | ----- | ----- | --------- |
| 1         | 1/27/2022 15:00 | poem  | apple | carrot    |
| 3         | 1/25/2022 13:00 | poem  | apple | ginger    |

我不知道如何通过 child 找到这些行。我写了这个 SQL 并卡住了：

select * from example_1 where merit in ('behaviour', 'poem')

这里需要分区吗？

Answer 1

一个可能的解决方案是使用 LEFT OUTER JOIN 将 table 连接到自身，然后仅接受 table returns 的连接版本为空的记录：

SELECT e1.* 
FROM example_1 e1
   LEFT OUTER JOIN example_1 e2
       ON e1.fruit = e2.fruit
       AND e1.vegetable <> e2.vegetable
       AND e2.date BETWEEN DATEADD(HOUR, -4, e1.date) AND e1.date
       AND e2.merit = 'behavior'
WHERE e1.merit = 'poem'
   AND e2.child_id IS NULL

诀窍主要在于加入条件，我们要确保在 'behavior' 和 'poem' 之间匹配 vegetable，同时还要检查最后 4 小时。

Answer 2

在这种方法中，我们使用整理子查询。顶级查询 B 为所需结果定义了 non-join 数据限制。所以蔬菜<>黄瓜和优点=诗

Exists 确保定义了第一行的限制并且存在不匹配项的相关性。所以我们确保水果匹配，优点是 'behavior'，child_id 的匹配，无论哪种方式，日期差异都在 4 小时内。

DEMO-DB Fiddle UK

SELECT B.* 
FROM table B
WHERE vegetable <> 'cucumber'
  and merit = 'poem'
  and exists (SELECT 1 
              FROM Table A
              WHERE A.Fruit = B.Fruit
                AND A.Child_id = B.Child_ID
                AND A.merit = 'behaviour' 
                AND abs(Datediff(hour,A.Date,B.Date)) <=4)

给我们：

+----------+-------------------------+-------+-------+-----------+
| child_id |          date           | merit | fruit | vegetable |
+----------+-------------------------+-------+-------+-----------+
|        1 | 2022-01-27 15:00:00.000 | poem  | apple | carrot    |
|        3 | 2022-01-25 13:00:00.000 | poem  | apple | ginger    |
+----------+-------------------------+-------+-------+-----------+

MSSQL 查询：如何按每个分区查找不正确的行？

MSSQL query: how to find the incorrect row by each partition?

sql

tsql

sql-server